Changes of blood flow in posterior cerebral artery in fetus with complete transposition of great arteries by pulsed Doppler ultrasound

Objective To study the changes of blood flow in posterior cerebral artery (PCA) in complete transposition of great arteries (CTGA) through the application of the pulsed Doppler. Methods Twenty CTGA fetuses(CTGA group) and 20 healthy control fetuses (control group)were involved, the blood flow indexes peak systolic velocity (Vs), end-diastolic velocity (Vd), pulsatility index (PI), resistance index (RI), velocity-time integral (VTI) of PCA-S1, PCA-S2 and MCA of the fetuses in the two groups were detected by pulsed Doppler. The differences in blood flow indexes between CTGA fetuses and healthy controls were analyzed by independent t-test. The rates of abnormal resistance in PCA-S1 and MCA in CTGA fetuses were compared through Chi-square test (χ2 test). Results Compared with control group, the MCA-PI, MCA-RI, PCA-S1-PI and PCA-S1-RI of CTGA group decreased significantly(all P 0.05). The rate of abnormal resistance in the MCA was significantly lower than that in the PCA-S1 in CTGA group (P<0.05). Conclusions The pulsed Doppler can be used to study the changes of blood flow in PCA of CTGA fetuses and the differences of specific hemodynamic alterations may occured in different segments of the PCA in CTGA fetuses, indicating a tendency to protect the PCA-supplying areas of the brain when ischemia and hypoxia. Key words: Ultrasonography, prenatal; Pulsed Doppler; Complete transposition of great arteries; Fetus; Posterior cerebral artery; Middle cerebral artery